The present disclosure relates to a method for processing a product by phase separation. The present disclosure thus relates to a method for processing a product by phase separation into two liquid phases and a solids phase. The method step includes processing the product, the processing occurring in a continuously operating centrifuge arranged as a separator, the separator including a rotatable drum having a vertical rotational axis, a disk stack having risers arranged in the drum, a product feed tube, a first separation disk for discharging a lighter liquid phase, a second separator disk for discharging a heavier liquid phase, solids discharge openings for discharging a solids phase from the drum, and a separation zone formed between the lighter liquid phase and the heavier liquid phase in the separator.
DE 10 2005 021 331 A1, DE 697 12 569 T2 and WO 94/06 565 A1 are mentioned concerning the technological background. DE 10 2005 021 331 A1 shows a purifier, but the discharge of a heavier liquid phase occurs by an outlet to which a throttle device is assigned and only the discharge of a lighter liquid phase occurs by a separation disk. WO 94/06 565 A1 discloses a purifier in which the lighter liquid phase occurs by a separation disk and the other heavier liquid phase occurs by a discharge apparatus using small tubes that are obliquely adjustable in relation to the radial, which small tubes are set once to the desired radius, so that the discharge of this phase will always occur in operation, but such that only a part of the small tubes immerses into the heavy phase, which is intended to keep friction at a low level. DE 697 12 569 T2 discloses a purifier in which the lighter liquid phase occurs by a baffle plate and the other heavier liquid phase by an outlet element which is pressed by a drive apparatus to varying locations of a free liquid surface area, so that the discharge of this phase will also always occur in operation, wherein the immersion depth in this phase shall be kept constant to the highest possible extent in order to reduce power consumption.
In the operation of purifiers, problems with the continuous discharge of the heavier phase will occur especially when the fraction of the heavier phase relative to the lighter phase is very low, that is, when the fraction of the heavier phase in the incoming product is less than 3%, or, for example, less than 1%.
The embodiments of the present disclosure address the solving of the above-noted problems in a simple way.
Thus, embodiments of the present disclosure relate to a method for processing a product by phase separation into two liquid phases and a solids phase. The method steps include processing the product, the processing occurring in a continuously operating centrifuge arranged as a separation, the separator including a rotatable drum having a vertical rotational axis, a disk stack having risers arranged in the drum, a product feed tube, a first separation disk for discharging a larger liquid phase, a second separator disk for discharging a heavier liquid phase, solids discharge openings for discharging a solids phase from the drum, and a separation zone formed between the lighter liquid phase and the heavier liquid phase in the separator, and, discharging the lighter liquid phase continuously and the heavier liquid phase discontinuously from the drum. Thus, the heavier liquid phase HP and the solid phase will be discharged only discontinuously, whereas the lighter liquid phase LP will be guided continuously from the drum.
As a result, a sufficient quantity of the heavier phase can accumulate at first further outside in the drum during operation until it is possible to discharge this quantity of the heavier phase from the drum. The discharge will then be interrupted for a specific period of time until a sufficient quantity of the heavier liquid phase has accumulated toward the outside in the drum in order to discharge it from the drum. In addition, the solids phase can also be ejected discontinuously from the drum, for example, in a manner which is independent of the time of the discharge of the heavier liquid phase, that is, by the solids discharge openings which are displaceable by a piston slide valve.
The method in accordance with the embodiments of the present disclosure can be used advantageously in the processing of vegetable or animal oils and fats which have a relatively low fraction of heavier phase, for example, less than 3%.
Embodiments of the present disclosure are discussed herein and in the appended claims.
Other aspects of the present disclosure will become apparent from the following descriptions when considered in conjunction with the accompanying drawings.